Drawer Bottom on deep drawer

[Andrew Pitonyak]

I am building drawers with an inside dimension of roughly 15.5" wide by about 26" deep.

There are three different drawer heights; roughly 4", 7", and 10" tall.

My initial intent was to make all of the drawer bottoms from 1/2" plywood, but, for the 4" tall drawer, is 1/4" likely to be sufficiently thick?

[Ole Anderson]

Will a 1/4" difference in depth really make a difference in the usability of the drawer? I would opt to go with 1/2" bottoms on everything.

[Rich Engelhardt]

How thick is the 1/4" material?
The undersized,, *** 1/4" *** ,,crud I see on the shelf @ the borg is way too flimsy.

[Andrew Pitonyak]

How thick is the 1/4" material?
The undersized,, *** 1/4" *** ,,crud I see on the shelf @ the borg is way too flimsy.
Good point.... I was thinking about using the 1/4" material because I managed to get a bunch of 1/4" Oak faced stuff for about $0.50 a piece... and each piece is probably about 1/3 to 1/4th of a sheet. I was looking to use it up. It was from the borg, however, so it probably falls under the category that you mention. It is MDF core.

My other 1/2" plywood is either cherry or mahogany.... Well, I don't know how much mahogany I will have left over, I need to "use what I need" first.

[Andrew Pitonyak]

Will a 1/4" difference in depth really make a difference in the usability of the drawer? I would opt to go with 1/2" bottoms on everything.

For sure it is not about the extra depth. To date I have only used 1/4" ply for bottoms on much smaller drawers. Worked great on 14" wide by 6" deep (no surprise).... My last set was probably closer to 9" wide by 12" deep. No problems in either case.

[Peter Quinn]

If the material were 1/4" Baltic birch, I say ok. But 1/4" veneer face MDf? I think you are pushing it at that span. Perhaps if you work in a support bar front to back from underneath to cut the span in half you could make it work.

[Jeff Duncan]

OK I have 2 thoughts on this, my first is in general I make all my drawer bottoms out of 3/8" material. Reason being is that is the largest groove I can make that will fit between the dovetails on my boxes, and it's strong enough for most normal sized drawers.

My second thought is more specific to your situation. If you already have a bunch of material your just looking to use up then I'd go ahead and use it. If it seems too flimsy you can do a couple things. One method is old school....you glue some thin hardwood strips across the bottom to re-enforce it....simple but works like a charm;) Second option would be to double up the 1/4" to get your 1/2" bottoms. Ideally if you had a vac press you could glue them together for the most rigid panel. However even without gluing them if you sandwhich two panels together you'll still increase the load capacity of your drawers.

good luck,
JeffD

[Andrew Pitonyak]

Sounds good.... So expect that the 1/4" I have is insufficient as is and so I either support (double, add something to strengthen), or I use the thicker. Thanks!

[Alden Miller]

I'd go with what Jeff suggests and glue the 1/4" sheets together (that's the cheapskate in me). I had a bunch of 1/2" ply that was too narrow to use for most things I wanted. I cut them to 32" lengths and glued them together to make very sturdy shelving stock...

-Alden

[Alan Bienlein]

1/4" is plenty strong for bottoms in a drawer that size. I have 1/4" for drawer bottoms in drawers that are at least twice that width and have had no problems. Unless you plan on stepping inside the drawer for some odd reason your 1/4" will be just fine.

[Andrew Pitonyak]

1/4" is plenty strong for bottoms in a drawer that size. I have 1/4" for drawer bottoms in drawers that are at least twice that width and have had no problems. Unless you plan on stepping inside the drawer for some odd reason your 1/4" will be just fine.

In other words, you are suggesting that it is at least worth testing.... Worth a test, should be easy to do.

[Darius Ferlas]

Unless you are planning to store tools, books and such in those drawers, 1/4" is more than enough.
I made a couple of drawers of somewhat similar size - 35" x 20" and 9" deep. I used 1/4" too.

[Jim Neeley]

Assuming you'll be insetting the bottom in a groove that's up from the bottom, install the 1/4" and try it. In the space between the bottom and the runners you can always glue in another piece. You don't need the bottom inset in the sides, just up near them to prevent sagging.

Another approach is to use 1/2" BB plywood and cut a rabbet around the perimeter down near 1/4". This lets you use a groove mount bit not lose too much depth while still leaving the extra 1/4" of drawer side stock to keep the bottom from breaking loose.

Jim

[Alan Bienlein]

In other words, you are suggesting that it is at least worth testing.... Worth a test, should be easy to do.
Yes that's what I'm saying. You'll be fine using it.

[Charles Wiggins]

I am building drawers with an inside dimension of roughly 15.5" wide by about 26" deep.

There are three different drawer heights; roughly 4", 7", and 10" tall.

My initial intent was to make all of the drawer bottoms from 1/2" plywood, but, for the 4" tall drawer, is 1/4" likely to be sufficiently thick?

Andrew,

For me it would all depend on what was going to be stored in the drawers. If these are general purpose drawers for that would hold clothes or pots and pans a decent 1/4" hardwood ply (not the BORG stuff) should be fine. If they are shop drawers I would do 1/2" ply on the 10" deep but probably stick with 1/4" luan on the 4" and 7" UNLESS I was going to store a lot of hardware, or my gold bar collection in them.

[Andrew Pitonyak]

Andrew,

For me it would all depend on what was going to be stored in the drawers. If these are general purpose drawers for that would hold clothes or pots and pans a decent 1/4" hardwood ply (not the BORG stuff) should be fine. If they are shop drawers I would do 1/2" ply on the 10" deep but probably stick with 1/4" luan on the 4" and 7" UNLESS I was going to store a lot of hardware, or my gold bar collection in them.

The 7" and 10" drawers will be 1/2" for certain.

For the 4" drawer, I will likely store things such as pencils, remotes, and my entire stash of gold bricks (which sadly means no gold bricks). This is for a computer desk.... There is sufficient height, that a computer mouse may be dropped in, perhaps some cables, screws, or a hard drive or two.

[Andrew Pitonyak]

...you can always glue in another piece. You don't need the bottom inset in the sides, just up near them to prevent sagging.

Had not considered that..... If it does sag, I can easily fix it after the fact....

Also, for these drawers, I plan on NOT capturing the bottom so that I can remove a screw in the back and remove the bottom. I have done this both ways....

These drawers will use metal side mount drawer slides (full extension with over travel), so there would be no problem dealing with it in the future if needed....

[Alan Bienlein]

You all over think this. !/4" is plenty for a drawer bottom. Here is a picture of a drawer in my kitchen that is 9-1/4" tall by 22" deep by 25-1/4" wide over all with 1/4" BORG plywood for the bottoms and 1/2" BORG plywood for the sides.
260865

[Willem Martins]

1/4" is plenty strong for bottoms in a drawer that size. I have 1/4" for drawer bottoms in drawers that are at least twice that width and have had no problems. Unless you plan on stepping inside the drawer for some odd reason your 1/4" will be just fine.

+1

I have just finished four filing drawers on a commission piece 13 x 20 and 11 deep, using 1/4" Maple veneer core ply, 1/2" maple for the box and a 3/4 Cherry false fronts. Through dovetails. They are heavy and solid compared to anything available retail. If I don't use under-mount slides, I rabbet the bottoms and glue the 1/4" ply into the box, using either clamps or brads. Don't think I have ever used more than 1/4" for the bottoms.

[Erik Christensen]

I have a leigh dovetail jig so I can hide any thickness groove. I use 1/2" ply for 100% of the drawers I make for the following reasons: the 1/4" loss of depth is not important in any drawer I have built, all drawers are basically bomb proof no matter how they end up getting used, purchasing is easier with just a single thickness to deal with and once the shaper is setup to cut 1/2" groove it is easier/faster to run everything through it rather than having to do a second setup for 1/4".

[Dave Zellers]

I used to be a 1/4" bottomer, now I'm a 1/2" bottomer for the reasons Erik listed.

[George Gyulatyan]

If this was a 1/4" baltic birch plywood, or even decent "regular" plywood, I'd probably go for it with an added reinforcement going through the center of the bottom of the drawer, front to back.
1/4" MDF? I wouldn't bother. By the time you reinforce it sufficiently enough, you'll end up spending more time and money than it's worth the $.50.

Go thicker. Go plywood.

[Dave Zellers]

I used to be a 1/4" bottomer, now I'm a 1/2" bottomer for the reasons Erik listed.
I'm sure if I was doing a series of small drawers, I'd use 1/4" but like others are saying, it would need to be good sturdy plywood.

[Andrew Pitonyak]

I checked my scrap from the build and I have enough left-over 1/2" mahogany ply for five of the six drawers. This is some really nice looking stuff. Feels like a sin to drop them in to the mixture of hard maple (sides and fronts) and poplar (backs). I will apply a front face that is mahogany.

[Zach Callum]

You all over think this. !/4" is plenty for a drawer bottom. Here is a picture of a drawer in my kitchen that is 9-1/4" tall by 22" deep by 25-1/4" wide over all with 1/4" BORG plywood for the bottoms and 1/2" BORG plywood for the sides.
260865


I second this. 1/4" is strong enough.

[Dave Zellers]

The drawer carrying the most weight in a kitchen is usually the silverware drawer.

But then, it's often a narrower drawer. I think the OP was for a desk drawer which usually carries little weight.

[Richard McComas]

For many years I've used 1/4'' drawer in 95% of all my drawers. I use BB plywood, it's just a fuzz under a full 1/4" and fits a 1/4'' dado perfectly. All my kitchen and shop drawers are 1/4'' BB plywood.

My unscientific testing includes having my 120 pound wife stand in the middle of 22 x 45 in drawer. I measured a deflection of 1/4'' in the middle of the drawer. In my test, I figure a drawer with 100 pound rated drawer slides the slides would Vail before the 1/4'' bottom would. Again unscientific.

In my day job (maintenance carpenter for our School District) we have 10's of thousands of drawer in the more that 100 schools and support building. In 15 years I can't remember have to replace a drawer bottom failure unless the drawer joints gave way first. The very few that have need repair are the ones made of Melamine.


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[Dave Zellers]

Sounds to me like we could put this issue to rest by all agreeing to use 3/8"!

:D

[Rick Fisher]

Ha.. i was going to suggest 3/8" Baltic Birch.. My workbench has 12 drawers under the work surface .. The bottom drawers are only about 18" wide but hold woodworking stuff.. planes, brad nails etc.. All drawers are 3/8" Baltic Birch .. No problems.

1/4" Baltic is great for drawers. Otherwise 3/8" or 1/2" for wider drawers..

Baltic Birch is the answer for drawers.. Its actually not that expensive if you consider how much per drawer your spending...

[Rich Engelhardt]

UPDATE


I am building drawers with an inside dimension of roughly 15.5" wide by about 26" deep.

There are three different drawer heights; roughly 4", 7", and 10" tall.

My initial intent was to make all of the drawer bottoms from 1/2" plywood, but, for the 4" tall drawer, is 1/4" likely to be sufficiently thick?
Ok -- update...

I made a box that fits under the top of my table saw's right extension's insert. The insert is "hinged" so I can swing it up to get access to the box. I store ZCI's and featherboards and other small table saw stuff in it.
The box is 1/2" thick MDF and is 4.5" high x 25" x 12" - nearly the same size as Andrew's 3" deep drawer.

For the bottom I used a piece of 1/4" (borg) birch ply.
It's - ok - not great but ok.
I'd feel better about it if it was 3/8" or 1/2" - which I would have used except for the fact that the scrap MDF I used for the sides was only 4.75" wide & I didn't want to sacrifice the extra 1/4".
I plan to add a 1/4" brace across the bottom @ the midpoint.